Make the lock/unlock and Enter/Exit methods in Mutex and Monitor private so taht we always use the …

runtime/vm/service.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/service.h"
 
 #include "include/dart_api.h"
 #include "include/dart_native_api.h"
 #include "platform/globals.h"
 
@@ skipping 1273 matching lines @@
     intptr_t num_frames = stack->Length();
     for (intptr_t i = 0; i < num_frames; i++) {
       ActivationFrame* frame = stack->FrameAt(i);
       JSONObject jsobj(&jsarr);
       frame->PrintToJSONObject(&jsobj, full);
       jsobj.AddProperty("index", i);
     }
   }
 
   {
-    MessageHandler::AcquiredQueues aq;
-    isolate->message_handler()->AcquireQueues(&aq);
+    MessageHandler::AcquiredQueues aq(isolate->message_handler());
     jsobj.AddProperty("messages", aq.queue());
   }
 
   return true;
 }
 
 
 static bool HandleCommonEcho(JSONObject* jsobj, JSONStream* js) {
   jsobj->AddProperty("type", "_EchoResponse");
   if (js->HasParam("text")) {
@@ skipping 366 matching lines @@
 
 static RawObject* LookupHeapObjectMessage(Thread* thread,
                                           char** parts, int num_parts) {
   if (num_parts != 2) {
     return Object::sentinel().raw();
   }
   uword message_id = 0;
   if (!GetUnsignedIntegerId(parts[1], &message_id, 16)) {
     return Object::sentinel().raw();
   }
-  MessageHandler::AcquiredQueues aq;
-  thread->isolate()->message_handler()->AcquireQueues(&aq);
+  MessageHandler::AcquiredQueues aq(thread->isolate()->message_handler());
   Message* message = aq.queue()->FindMessageById(message_id);
   if (message == NULL) {
     // The user may try to load an expired message.
     return Object::sentinel().raw();
   }
   if (message->len() > 0) {
     MessageSnapshotReader reader(message->data(),
                                  message->len(),
                                  thread);
     return reader.ReadObject();
@@ skipping 2404 matching lines @@
     if (strcmp(method_name, method.name) == 0) {
       return &method;
     }
   }
   return NULL;
 }
 
 #endif  // !PRODUCT
 
 }  // namespace dart